Lean 4 Proof Engineer – Mathematical Formalization
$170–200/hr
Remote math contract with Alignerr, $170–200/hr. Posted Oct 22.
$170–200/hr
Apply on AlignerrIs this job worth applying to?
- Pay
- Above typicalTops out at $200/hr. The typical top rate across 47 priced math listings is $90/hr.
- Getting in
- Hard to get in~1–2 hours of assessments. Valid government photo ID.
- Steady work
- Work is patchyFeast-or-famine project volume.
- Payout record
- Some delaysSchedule: weekly, by Friday for the prior Monday–Sunday. Paid via Stripe or PayPal (depends on country).
- Freshness
- RecentPosted 2w ago. Still listed on Alignerr on Nov 6, 2026.
- Where you live
- Not statedThe listing names no country.
The job description
About the Role
What if your deep mathematical training could directly shape how AI understands and reasons about formal proof? We're looking for skilled mathematicians and formal verification specialists to translate advanced mathematical arguments into machine-verifiable Lean 4 proofs — working at the frontier of what proof assistants can express, capture, and automate.
This is a fully remote, flexible contract role. If you live for rigorous proof construction and find satisfaction in the precision of formal systems, this is the role built for you.
What You'll Do
- Translate informal mathematical proofs into clean, structured, machine-verifiable Lean 4 formalizations
- Analyze proofs across domains — identifying gaps, hidden assumptions, and formalizable sub-structures
- Construct formalizations that test and extend the limits of existing proof assistants
- Investigate where automated provers break down and articulate the underlying reasons — complexity, missing lemmas, library gaps, and more
- Collaborate with researchers to design and refine formal verification strategies
- Develop highly readable, reproducible proof scripts aligned with mathematical best practices and proof assistant idioms
- Provide expert guidance on proof decomposition, lemma selection, and structuring techniques
- Formalize classical proofs and compare machine-verifiable structures against textbook arguments
- Create Lean proofs that reveal deeper patterns or generalizations implicit in the original mathematics
Who You Are
- Hold a Master's degree or higher in Mathematics, Logic, Theoretical Computer Science, or a closely related field
- Have a strong foundation in rigorous proof writing across areas such as algebra, analysis, topology, logic, or discrete mathematics
- Have hands-on experience with Lean (Lean 3 or Lean 4), Coq, Isabelle/HOL, Agda, or comparable proof systems — Lean 4 strongly preferred
- Deeply enthusiastic about formal verification, proof assistants, and the future of mechanized mathematics
- Able to translate informal arguments into clean, well-structured formal proofs with precision and clarity
Nice to Have
- Familiarity with type theory, the Curry-Howard correspondence, and proof automation tools
- Experience contributing to large-scale formalization projects such as Mathlib
- Exposure to theorem provers in contexts where automated reasoning frequently requires manual scaffolding
- Prior experience with data annotation, data quality, or AI evaluation systems
- Strong communication skills for explaining formalization decisions, edge cases, and reasoning strategies
Why Join Us
- Work on cutting-edge AI research projects alongside leading labs and research teams
- Fully remote and flexible — work when and where it suits you
- Freelance autonomy with intellectually stimulating, frontier-level work
- Contribute directly to how AI systems understand and reason about advanced mathematics
- Potential for ongoing work and contract extension as new projects launch
How do you apply to Alignerr?
Apply on Alignerr
The Apply button opens this post on Alignerr's own site. You apply with them, not with Rubric. Budget about 1–2 hours of assessments.
Get through screening
What Alignerr asks for after you apply:
- Take the TestGorilla skills assessment (usually one attempt per role)
- Verify your identity with Persona
- Join the Alignerr Slack community
- Set up payouts once you are assigned to a project
Start work and get paid
Pay schedule: weekly, by Friday for the prior Monday–Sunday. Paid via Stripe or PayPal (depends on country). You're paid for the work they hand out, not a fixed salary.
Alignerr also needs
- Valid government photo ID
- Degree or professional experience for expert roles
- Webcam for proctored assessments on some roles
Red flags
- Red flagLong gaps with no project after passing
- Red flagWorker reports of delayed or withheld payments on Glassdoor
What is Alignerr like to work for?
Labelbox's contractor network, which hires generalists and domain experts to label data and write and grade AI training tasks.
| Advertised pay | $15–150/hr |
|---|---|
| Getting in | Hard to get in |
| Application takes | ~1–2 hours of assessments |
| How you get paid | Weekly, by Friday for the prior Monday–Sunday, via Stripe or PayPal (depends on country) |
| Payout record | Some delays |
| Countries | Accepts most countries but blocks signups from about two dozen; posts India-specific roles such as Hindi, Telugu and Indian-English language and cultural review work. |
Generalist and bilingual work is around $15–20/hr, coding QA $30–40/hr, and senior software, advanced math, medical and law roles $70–150/hr; some projects pay per approved task.
